It was alleged that the saturated fat increased the cholesterol level in the blood and therefore increased the risk of developing heart disease. This has never been reliably substantiated.
Although there is no scientific rationale for including carbohydrates in the diet, the deficit in fat had to be replaced by carbohydrates.
Here in the UK, the advice from the authorities is to “base meals on carbohydrates” so that at least 50 per cent of the diet must be carbohydrates in order to comply with the official guidelines.
Although the diet-heart hypothesis has now been totally discredited, governments all over the world continue to promulgate this fundamentally flawed official advice.
There never was universal agreement that the focus of the dietary guidelines should have been on the reduction of fat.